—Someone is knocking at the door. Is it Ann?

Someone is knocking at the door.____ is it? someone is knocking at the door.who [ ]it be? ---someone is knocking at the door.Who _____ it be? -----Someone is knocking at the door.It ____ be Tom . --Listen! Someone is knocking at the door. Someone is knocking at the door.Who it be?— It be Tom.He is Someone is knocking at the door.___ it be Venis?—No,it ___ b someone is knocking at the door,who is it? A this is a polic someone is knocking at the door （）i go and see who it is A s someone is knocking at the door .（）i go and see who it is A Open the door!Someone is knocking at it.It _____ Mr Zhang.He Someone is knocking at the door,but who can____ be?